(1) Field of the Invention
This invention pertains to the conversion of hydrocarbons, especially hydrotreating them, in the presence of a catalyst composite. This invention also pertains to removing metals, especially contaminant metals, from spent hydrotreating catalysts.
In the process of this invention, metals on the spent catalyst are removed by first contacting the catalyst with a specific type of complexing agent. Then, a mixture containing the complexing agent and the removed metals is separated from the spent catalyst. Afterwards, the spent catalyst with the contaminant metals removed may be further treated to restore the catalyst to its fresh, or nearly fresh, state. Or the spent catalyst minus the removed metals may be disposed of, in a landfill, for example, with less worry that the contaminant or catalytic metals will be leached from the landfill to pollute ground water supplies. Also, the mixture containing the complexing agent and the removed metals may be treated to extract and collect from it valuable contaminant or catalytic metals.